Why are barns red? Why is New York called the Big Apple?

Whilst cruising through the countryside the other day, I noticed that most of the barns were painted red. Why is this? Also, what is the origin of the New York City nickname, the Big Apple?

— Marsha N., Baltimore

Cecil replies:

Barns were originally painted red because back in pioneer days there wasn't much choice. Farmers used to make their own mixture, consisting of a nauseating blend of skim milk, lime, linseed oil, and iron oxide, better known as rust. "Hmm," said the anonymous inventor of this concoction, "this is not the milkshake I hoped it would be. But it might make a pretty good paint."

It was even so. The mixture hardened quickly and wore well. The red color was a side product of the iron oxide. After the advent of Sears Roebuck and modern factory-mixed paint, barns stayed red in order not to disappoint the tourists.

The etymology of "Big Apple," sad to say, lacks the classic clarity of the answer to the first part of your question. Of the many theories advanced, the most reasonable seems to be that the phrase originated in show-biz circles. "There are many apples on the tree," an old saying supposedly runs, "but only one Big Apple." So vaudevillians, jazzmen, and other wormy entertainment types dubbed New York, the most important performing venue of them all, the Big Apple. (For an update on this answer,click here.)